The invention relates to a gas separator for liquid-conducting systems, as independent appliance or as integrated component of in-line pumps, especially circulating pumps for heating and cooling installations, with inlet and outlet pipes for the liquid lying on one common center line and with a substantially cylindrical separation chamber arranged between the two pipes, into which chamber the liquid-gas mixture is introduced tangentially and set in rotation, by appropriate flow guidance, about the axis of the chamber forming a center of rotation, the gas being forced towards the center of rotation and conducted away to the exterior while the degassed liquid flows away out of the chamber through a separate outflow opening.
Especially in pump installations, air or gas in the liquid to be delivered is the cause of many troubles which can be divided essentially into two groups. The first group of troubles concerns problems of the installation itself, such for example as inadequate lubrication of bearings if the pump delivers oil foam, or as noise generation in heating installations due to air bubbles conveyed with the water flow. The second group of troubles referred to concerns the function of the pump and its safety. In this context it is known that the throttle curve falls with the gas proportion and operation of the pump in the part-load range causes difficulties because even slight faults on the suction side of the pump can lead to break-away of the delivery flow.
If the gas or air bubbles then unite in the installation into a larger volume and the large gas bubble then occurring, for example by reason of regulating actions, passes with the delivery flow into the impeller of the pump, failure of the pump is ordinarily to be expected. In the centrifugal field of the impeller in fact the gas volume is displaced towards the axis of rotation, where it blocks the suction side so that delivery is suppressed.
This situation is especially disadvantageous when wet-running circulating pumps for heating installations are concerned, the bearings of which are thus lubricated by the delivery flow. The gas bubble situated in the center of rotation then in fact blocks the access of liquid to the bearing, which thus runs dry. Dry-running bearings, however, are quickly destroyed, so that the pump and thus also the heating system will fail.
This problem is generally known in circles of the art, so that various gas separators, based upon the gravity or centrifugal principle, have been developed as independent appliances or equally pumps with suction housings of special configuration. In this connection reference can be made to German Publication Specification Nos. 1,653,727, 1,937,119 and 2,810,583. Separate separators usually have the disadvantages that they cannot be installed independently of position, they are of relatively large construction and are also expensive. The known special pumps are likewise subject to the same limitations of installation and further have the disadvantage that the degree of separation is very much dependent upon the delivery flow, so that the mentioned troubles in pump installations could not hitherto be eliminated.